Wrapped product and method and apparatus for producing same



May 1, 1962 R. MUSKAT ETAL WRAPPED PRODUCT AND METHOD AND APPARATUS FOR PRODUCING SAME 2 Sheets-Sheet l Filed NOV. 17, 1958 n@ Sw 'Z2/ a wwwa? K Olaf 36C Z fia May 1, 1962 L.. R. MUsKAT ETAL 3,031,809

WRAPPED PRODUCT AND METHOD AND APPARATUS FOR PRODUCING SAME 2 Sheets-Sheet 2 Filed NOV. 17, 1958 3,031,809 WRAPPED PRODUCT AND METHOD AND APPA- RATUS FOR PRODUCING SAME Louis R. Muskat, 814 Timberline Drive, and Robert L. Muskat, 612 Hill Circle, both of Glenview, Ill. Filed Nov. 17, 1958, Ser. No. 774,312 6 Claims. (Cl. 5330) This invention relates generally to a method of packa mg.

gThe method comprises the use of a generally flat blank positioned within transparent wrapping material formed of heat scalable sheeting such as rubber hydrochloride, commonly sold under the trademark Pliotilm, cellophane or the like. Sheet materials, of which Plioiilm is an example, are not only heat scalable but are adapted to be expanded or stretched and also to be contracted, which qualities, as will be explained in detail later, are utilized in the packaging operation when necessary.

The products to be wrapped are such as are generally sold in supermarkets and other stores which offer for sale a large variety of products, including meat, poultry, fruits, vegetables, etc. Products of these types vary greatly in size, shape and thickness or depth. Because of this wide variation in the sizes, thicknesses, and shapes of the products to be packaged, it has heretofore been the practice to use square sheets of material of many different sizes and to place an appropriate size product-holding tray or paper-board blank on the sheet, thereafter to wrap the wrapping sheet around the product and tray in which the product is placed or around a relatively stiff paperboard blank on which the product isplaced.

The wrapping of such products entails an initial manual operation of forming at least part of the wrapper around the tray or blank and product and in sealing overlapping marginal portions of the sheet together. Although it was possible thereafter to complete the wrapping operation by means of automatic machinery the necessary initial manual operations consume a considerable amount of time and are dependent upon the dexterity of the individual to a large extent. Also the character of the tinished wrap varies to a considerable extent, depending upon the skill of the operator.

In the wrapping of packages of this type, it is desirable that the wrap tightly envelop the products as a loose wrap tends to permit greater deterioration of the product, particularly if the product be meat, fowl, vegetables or the like.

Again, since the prepackaged goods are on display in the store and are to be selected by the purchaser, a smooth, tight Wrap is particularly desirable in order to enhance the appearance and hence better promote the salability of the product. These various factors of size, shape, thickness, etc. of the product have heretofore required the packager to keep in stock or inventory a large number of different size trays, wrapper sheets, blanks, etc., in order to accommodate the various products to be packaged.

An object of the invention is to provide a method whereby the product to be wrapped can be quickly and easily enveloped and sealed within sheet wrapping material.

Again, it is an object of the invention to provide a method and apparatus for practicing the same whereby the blank of the wrapper article may, during the packaging operation, be converted from relatively at form into tray-like formation.

Still another object of the invention is to provide a method for shrinking the wrapping material about the enclosed product in order to form a tighter wrap.

It is also an object of the invention to provide a tray,

ice

contained product and enveloping wrapper in which the tray sides of the completed package also function to exert tension on the wrapper sheet, thereby assisting in maintaining a tight wrap even though the enclosed product may shrink or be slightly compacted during storage or display.

Further objects of the invention and the advantages thereof will be obvious from the following description and drawings which show apparatus facilitating the practice of the method.

In the drawings:

FIG. l is a schematic view in elevation V of apparatus which may be use to facilitate practicing the method of the invention, certain of the parts being shown in a second position by means of dotted lines.

PIG. 2 is a view similar to FIG. l, but illustrating certain parts ofthe apparatus in a different relative position.

FIG. 3 is a perspective view of one form of wrapper article which may conveniently be used practicing the invention, a stack thereof being shown in the magazine of the apparatus illustrated in FIGS. l and 2.

lFIG. 4 is a fragmentary transverse vertical sectional View on the line 4-4 of FIG. l, viewed in the direction of the arrows, certain of the parts being shown in a second position by means of dotted lines.

FIG. 5 is a fragmentary transverse vertical section on the line -5-5 of FIG. 2, viewed in the direction of the arrows. p

lFIG. 6 is a view similar to FIG. 2 but showing the uppermost wrapper article in the magazine expanded for the reception of the product, certain of the parts being shown in different positions by means of full lines and dotted lines respectively.

FIG. 7 is a view similar to lFlG. 6 but showing the product and enveloping wrapper article disposed in the position for the closing of the entrance opening of the envelope portion of the wrapper article.

FIG. 8 is a fragmentary view illustrating the operation of sealing the openpart of the envelope and severing the excess marginal Wrapping material from the completed wrapped package.

FIG. 9 is a perspective view of the wrapped package. FIG. l0 is a vertical sectional View through the wrapped package on the line lll-lil of FIG. 9, viewed in the direction of the arrows, and l FIG. l1 is a vertical sectional view on the line 1li- 11 of FIG. 9, viewed in the direction of the arrows.

It should be understood that the method contemplates the use of a blank preferably of relatively stiff paper board, several forms of which are disclosed in our copending application Serial No. 774,313., iiled November 17, 1958.

The preferred form is that of a flat sheet of paperboard having marginal iiange portions bordering a central part, the lines of juncture being creased, scored, or weakened, thereby to` facilitate the folding of the liange portions relative to the central part of the blank, when the hat blank is to be converted into an open top tray.

As will be explained in detail later, the stiness of the tray or blank facilitates, to a certain extent, separating sections of the wrapper envelope which is necessary during certain stages of the operation of the method.

General Explanation of Invention By way of general explanation of the invention it should be understood a stack of wrapper articles, each comprising an envelope havinga relatively sti blank therein, is provided in a magazine, the wrapper articles being then in substantially flat form. FIG. 3 illustrates one form` of wrapper article. Means, in this instance a vacuum cup, is provided for lifting one section of the wrapper sheet as envelope away from the enclosed blank to somewhat enlarge the access opening to the interior of the envelope. Thereafter a pair of spreader plates S carried by reciprocable mechanism M is projected through the opening, after which the spreader plates are relatively separated in order to move sections of the envelope away from each other to provide a relatively deep envelope, such for example, as indicated in FIG. 6. Thereafter, the product P is pushed into place between the spreader plates as by ram R, the ram means continuing thereafter to move the wrapper article and the enclosed product to a position beyond the magazine station to a position adjacent a sealing and trimming station. At the sealing `and trimming station the open end of the Wrapper article is closed and sealed and the excess material removed by a trimmer knife, as indicated in the fragmentary View, FIG. 8.

As will be explained in detail later, in order to facilitate the stretching of the wrapper material so that a given size wrapper article will accommodate a number of product sizes, heat means such as I-I is provided for softening the iilm of wrapping material. Since itis also -a characteristics of the wrapping material which is preferably used in the practice of the method and which comprises'the envelope of the wrapper article, to shrink after having been heated, means HZ is provided for applying heat to the Wrapped package as indicated at theV right hand end of FIG. 7 and as will be explained in detail later.

It is believed that the foregoing general explanation will be adequate to facilitate an understanding of the various steps of the method; the apparatus utilized; the disclosed apparatus for practicing the method and the novel wrapped package resulting `from the practice of the method by means of the apparatus disclosed.

The Wrapper Article A wrapper article may be utilized in the practice of the invention and may be of the type disclosed in our said co-pending application Serial No. 774,313, now abandoned, tiled November 17, 1958. One form of such wrapper is shown in FiG. 3 of the instant application and comprises an envelope 2t) within which there is disposed the blank 21, preferably formed of sheet material which is stiff relative to the material of which the envelope is fabricated.

As by way of illustration, the blank may comprise a central portion 22, side flap portions 23 and 24, rear flap portion 2.5 and front flap portion 26, the purposes of which will appear later.

The envelope material is preferably of a transparent character to permit visual observations of the product when placed within the envelope and as here shown cornprises two rectangular sections 27 and 28 closed along three margins but being open along the fourth margin to provide an opening 29 in order to permit access to the interior of the envelope.

Not only is the material forming the envelope preferably transparent in character but itshould, for certain uses, have different qualities. For example, cellophane may be suitable under certain conditions. Thus, if the product to be wrapped or packaged is not of relatively great depth or thickness, it may be suicient simply to provide an envelope which is substantially larger than the area of the blank within the envelope so that upon relative separation of the sections 27 and 28 adequate space will be provided to accommodate the product, or the envelope may be substantially the size of the blank in flat form, the upfoldng of the marginal flap portions providing the necessary depth for certain products. On the other hand, if the product is of greater depth or thickness, andV it is desired to utilize a wrapper article of a given size, it is necessary to use a lm of a stretchable nature, of which rubber hydrochloride (commonly sold under the trademark Pliolm) is an example. Pliolm also has another advantage in that when subjected to mild heat the stretchability of the sheet material is substantially enhanced. Thus, by using stretchable material, a single envelope suflices to receive and package a wider variety of products as to size and particularly thickness than would be the case were the envelope made of non-stretchable stock and by the application of mild -heat to the envelope a much wider range of product sizes can be accommodated.

As has been indicated earlier in the specification a tight wrap is much desired. There are certain sheeting materials which, when subjected to mild heat, tend to contract or shrink., Thus, by subjecting the envelope of the wrapped product to heat after the product has been placed within the envelope, it is possible to shrink the material, thus causing a tighter wrap. Also, in those cases Where the blank comprises Hap portions which constitute tray walls in the finished package, the shrinking of the material tends to pull the flap portions into a position more nearly normal to the central partof the blank than would otherwise be the case, which action in turn causes an inherent tendency of the ap portions torreturn to the original plane to act as tensioning elements. Pliolm is one s uchy material and hence is a good illustration of a satisfactory type of sheeting material from which to fabricate the envelope.

It will be assumed in the further description of the invention, that the one who is to use the invention has selected the particular type of wrapper envelope best adapted to the needs of the particular products being packaged.

The Magazine Vfor the Wrapper Articles As here shown, the magazine for supporting the wrapper articles comprises a base plate 36 which can be raised and lowered by means of a plunger 31 operated by any suitable mechanism in such a way as to present a single envelope at the top of the stack in proper position and to hold the same in that position while the necessary steps are taken for the placement of the product Within the envelope.

The magazine, in addition to the plunger 31 and base plate 30, may comprise suitable walls 32, 33 which may be part of a table structure 34..

It should be understood that when the Wrapper articles are placed in the magazine they are in relatively iiat condition, as appears in full lines in FIG. 4 and conveniently disposed in a horizontal plane with the top 35 of the table 34 also disposed in a horizontal plane.

Means for Initially Separating Envelope Sections 27 and 28 The specific mechanism shown for this purpose comprises a cup-shaped member 38 attached to a tube 39, the tube 39 being guided for vertical reciprocatory movement by a suitable bearing 40. The tube 39 is connected to any suitable mechanism for creating at least a partial vacuum so that when the cup-shaped member :i3 is pressed against the upper section of the envelope and the tube 39 and cup 38 elevated to the dotted line posi tion FIGS. 1 and 4, the upper section of the envelope is moved', say, to the position shown in FIGS. l and 4 by dotted lines, and by full lines in FIG. 5. In this way there is provided an enlarged opening or mouth 29 of such size as will readily receive certain separator plates which comprise part of the mechanism for further expanding the envelope and which also serve as a support and guide for the placement of the product in the envelope.

Envelope Separating and Product Guiding Means This mechanism in the drawings is designated generally by the reference letter M.. It comprises a carriage 50 and means, not shown, for reciprocating the same in a horizontal plane toward and away from the magazine in which the wrapper articles are stacked.

Attached to one end of the carriage 50 is a fiat plate 51 which projects from one end toward and into close proximity to the magazine. The carriage 50 is guided in its to-and-fro reciprocatory movement by means of a bearing 52 which is slidable upon a horizontally disposed carriage guide rail 53.

The mechanism M also includes a flat plate 54 which, in one position is in intimate superposed relation to the underlying plate 51. The plate 54 is fixed to reciprocate vertically with a carriage member 55, attached to vertical members 56 which slide in bearings 57 xed to move horizontally with the carriage member 50. The two members 56 are cross-connected at the bottom by a member 58 to which vertical reciprocation may be imparted by any suitable means through the plunger 59.

By moving the carriage S toward the magazine while the plates 51, 54 are close together they can be quickly and easily projected into the envelope through the enlarged open margin thereof, as indicated in FIGS. 2 and 5.

Thereafter the plunger 59 may be actuated to raise the plate 54 relative to the plate 51 and thereby expand the envelope, as is illustrated in FIG.. 6. This having been done the product P is pushed into place by the plunger R so that the product P is moved from the full line positions shown in FIGS. 1, 2 and 6 to the dotted line position of FIG. 6.

lt will be understood that in the movement of the product from its initial position exteriorly of the wrapper article, to a position interiorly thereof, 'as shown in FIG. 6, the product moves between the separator plates 51 and 54, being supported` and sliding on the upper surface of the lower plate 51, at least during the final movement of the product into its assembly position within the wrapper article. In this connection it might be mentioned that the surfaces on which the product slides should preferably be of highly polished character and one which will not be adversely affected by contact with meats, poultry and the like which are products frequently packaged by the methods and mechanism of-the type herein disclosed. Thus, stainless steel is indicated as a material suitable for use in fabricating the parts mentioned. Other materials which can be given a sanitary iinish and having a surface on which the products will slide Vfreely may be used, the principal aim being to provide surfaces which will not olfer undue resistances to the movement of the product on its way into the wrapper article and which can be easily maintained in sanitary condition.

After the product has been positioned, as indicated by dotted lines in PIG. 6, the pusher R with the medium of the horizontally reciprocable rod R', is pushed to the position designated as T in the drawings, as indicated in FIG. 7. In the course of this movement it will be seen that the envelope, the blank therein and the enclosed product are stripped from the separator plates 51 and 54, this being permitted because the envelope is, at that time, open along one margin.

After the pusher rod R has delivered the product to the position or station T, it is returned to its initial position, as shown in FTG. 1 and the separator plates 51 are returned to the initial position shown in FIG. l, being thus ready for another cycle of operation.

Sealing and T rmmng Station From the foregoing description it will be understood that at the time the product and envelope arrive at the station T one margin is still open and unsealed. -In order to seal the final margin there is preferably provided sealing mechanism which may comprise an upper pinch bar 60 and a lower bar 61, together with means for causing approaching and separating movement thereof from the spaced position shown in FIG. l to the closed position shown in FIG. 8. The lower bar 61, as illustrated, is provided with a portion 62 which is heated, by means not shown, thereby sealingly uniting the marginal portion of the upper section 27 of the envelope to the lower section 28. A knife 65 is attached to the lower bar 61 and is provided and functions to trim the excess material from the extreme outer margins of the envelope sections sealed by the sealing means just described. Mechanism for sealing and trimming heat-and-pressure sealable material is well understood in the art and need not be described in further detail. It is also well known that materials like Pliolm are sealable in this manner and that other sheeting, of which cellophane is an example, is available with a coating or film thereon which makes it sealable by the application of heat and pressure.

Comments Re H eating Aspects As was explained earlier in the specication, some of the materials utilized are such that the stretchability of the envelope material is enhanced by mild heating. Plioflm is an example of such material. For this purpose an infrared electric heater H may be provided. Through suitable electrical controls the period of time can be accurately gauged and the magnitude of the heat supplied to such as will be sufiicient to heat the particular material to raise it to that temperature which will give the increased stretchability desired. This obviously will vary with the particular material employed. However, only a mild heat will be applied sufficient to provide increased stretchability `when that is required and not such as will destroy the sheet or film character of thesheet.

Earlier in the specilication it was also indicated that for certain purposes the shrinking of the envelope material might be the most important result desired. For this purpose a heater HZ has been provided, as schematically illustrated in FIG. 7. The heater HZ may, conveniently, be positioned beyondthe station T where the sealing of the open margins of the envelope occurs. This being the case, when pusher R moves the package into position to be sealed, the envelope and contained productuserve to push the immediately adjacent and completed package into position under the heating element HZ. f

The amount of heat to be applied by heater HZ is again a variable one but, in any event, the envelope will be only mildly heated, which will be suliicient to effect desired shrinkage of the envelope material.

Further Comments Re Operation of Method and Machine We have heretofore explained the general method of operation and also one form of the mechanism utilized in performing the method and some of the results obtained. While it was not specifically so stated, it will be understood that once the vacuum cup 3S has served to lift the upper section to the position shown in dotted lines in FIG. l and the separator plates 51 and S4 have entered the envelope, as indicated in FIG. 2, the suction may be discontinued since from there on the separator plates function to move the envelope sections without stretching the material of which the envelope is formed or, if need be, also stretching the envelope to the extent which is permissible and feasible without heating-the material. If still further deformation or stretchability is required the envelope is subjected to mild heat to accommodate the still wider separation of plates 51 and 54. In this way a given wrapper envelope is able to package a wide range of product sizes.

As is more fully developed in our co--pending application S.N. 774,313 tiled November 17, 1958, the wrapper article illustrated in FIG. 3 of this application may comprise a blank and an envelope and that the blank within the envelope may be a sheet of relatively stiff material having marginal flap portions adapted to be folded relative to the central portion in order to constitute the uprightwalls of a tray. It is possible that under certain conditions the lifting of the top section 27 of the envelope by the vacuum cup may operate to swing or fold certain of the flap marginal portions upwardly, more particu- `whether folding becaused by one or'both of these instrumentalities, the conversion of a relative ilat sheet into a tray in which at least certain of the iiaps extend upwardly results. However, due to the fact that the envelope is open along the margin beyond the flap 26, that Aparticular ap is not moved upwardly until there is presented an opening suilcient to permit the entrance of Vthe plates S1 and 54 into the envelope.

Thereafter, as is clear from FIG. 5, the lower plate 511, which is subi stantially the width of the central portion of the blank and hence coextensive in length with the length of the contiguous ap 26, prevents the upturning of that ange when the separator plates 51 are moved apart to'create the necessary space or depth for the reception ofthe particu- Vlar product being packaged.

After the envelope and the product have been stripped from the separator plates the iinal vupward movement of the marginal iiapvportions including that adjacent the Lopen margin ofthe ap occurs. vbars associated with the sealing operation move together 'the sheet material adjacent the flap along the open margin Vis drawn together so as to put tension on the sheeting :and to effect a nal upward movement of not only the Thus, when the pinch flap adjacent the portion of the tlap initially open, but

also, in Vsome instances, 'and to a certain extent, on some of the other flaps, depending upon the size of the product and its relation to the particular envelope being used. The completely wrapped product-is illustrated in perspective in FIG. 9 and in the cross-sections FIGS. 10 and 11 which, in the light of the foregoing remarks,lneed no 4further comment.

The many advantages of the invention will be understood by persons skilled in the art, without further comment.

Je claim: 1. A method of packaging comprising operating upon a product positioned on a blank of sheet material, both ythe product .and blank being enveloped in wrapping material and in which the blank comprises a central portion bounded bya plurality of peripheral flap portions, the included angle between the upper side of the central porr tion of the blank and the same side of the flap portions being greater than ninety degrees, which method consists in shrinking the enveloping wrapping material suiiciently to exert force acting to move the flap portions in a direc tion lmore nearly normal to the central portion of the `blank and subjecting the flaps to stress acting to establish and maintain tightness of the wrap.

2. The method set forth in claim l in which the blank Liov is formed of sheet material which is relatively stiff, as compared to the wrapping material. y'

3. A method of packaging comprising operating upon a product positioned on a blank of sheet material, both the product and blank being enveloped in wrapping lmaterial which shrinks when heated and in which the blank comprises a central portion bounded by a plurality of 'peripheral ilap portions, the included angle between the upper side of the central portion of the blank and the same side of the iiap portions being greater than ninety degrees, which method consists in subjecting the wrapping material to heat to cause suicient shrinking of the enveloping wrapping material to exert force acting to move the ilap portions in a direction more nearly normal to the central portion of the blank and subjecting the flaps to stress acting to establish and maintain tightness of the wrap.

4. The method set vforth in claim 3 in which the blank is formed of sheetmaterial which is relatively stii, as compared to the wrapping material.

5. A method of packaging comprising operating upon a product positioned on a blank of sheet material, both the product and blank being enveloped in Wrapping material and in which the blank comprises a central portion bounded on all sides by a plurality of .peripheral lap portions which extend upwardly and outwardly from the central portion, the included angle between the upper yside of the central portion of the blank and the same side of the flap portions being greater tharininety degrees, which method consists in shrinking the enveloping wrapping material suiiciently to exert force acting to move the llap portions in a direction more nearly normal to the central portion of the blank and subjecting the flaps to stress acting to establish and maintain tightness of the wrap.

6. The method set forth in claim 5 in which the blank -is formed of paperboard and the wrapping material is relatively thin heat-shrinkable nlm.

References Cited in the iile of this patent UNITED STATES PATENTS 2,486,762 Pfeiffer Nov. 1, 1949 2,506,057 Bergstein May 2, 1950 2,514,028 Cloud July 4, 1950 2,523,667 f j Palmer etal Sept. 26, 1950 y 2,554,636 Pfeiffer May 29, 1951 y 2,577,588 Paige Dec. 4, 1951 2,645,337 tenger July 14, 1953 2,668,403 Rumsey Feb. 9, 1954 2,708,028 Murphy et al. May 10, 1955 2,722,166 Keller Nov. 1, 1955 2,779,681 Sell et al. Ian. 29, 1957 2,785,519 Rurnsey Mar. 19, 1957 2,801,180 Rumsey July 30, 1957 2,815,624 Forry et al. Dec. 10, 1957 .2,852,133 Bonini et al. Sept. 16, 1958 `2,9sa245 Stoker Apr. 1s, 1961 

